Abstract

The fast improvement of the current technology requires unceasing development of manufacturing and processing of coating materials to produce better-molded material. NMLC promises an abundant solution to this problem, and Molecular Dynamic (MD) has been proven to be a powerful tool in studying NMLC [3]. By using MD simulation in this research, modulation period thin films were obtained based on the model of deposition, and the same modulation period was produced for the ideal thin film based mainly on their lattice constant. This research will aim to examine the structures and thermophysical characteristics of Cu/Ni thin films under a temperature gradient and to identify the vacancies and lattice mismatch of coating under thermal stress. The coherent lattice interfaces exist in all the Copper/ Nickel thin films after structure optimized via annealing. There are more vacancies obtained in the ideal thin films than via the deposition system. The vacancies/defect in the thin films will weaken its overall thermophysical characteristics. The lattice mismatch or the vacancies in all the system strengthen the mobility of atoms and lead to a higher temperature after the simulation.

Index Terms

Modulation, Molecular Dynamic, Temperature Gradient, Thin Films

Abstract

Small wind turbines suffer performance degradation due to its inherent low Reynolds number flow. The flow is initially laminar and is prone to separate even under a mild adverse pressure gradient. Recent studies revealed the capability of corrugated Dragonfly airfoil in delaying flow separation against streamlined airfoils in the low Reynolds number regime. Hence, this paper aims to improve the performance of small wind turbines by leveraging the capabilities of Corrugated Dragonfly airfoil. Experimental results have shown that small wind turbines made from corrugated dragonfly, NACA 4412, and flat plate airfoil had a coefficient of performance of 0.191, 0.284 and 0.099, respectively.

Index Terms

corrugated Dragonfly airfoil, low Reynolds flow, Qblade, small Horizontal Axis Wind Turbine (HAWT)

Abstract

LASER diffraction method is used in measuring small diameters like human hair by projecting the diffracted rays on a medium where fringe patterns can be seen and measured. This experiment demonstrated the application of LASER diffraction method by a single-slit to measure the diameter of a guitar string. The method was also used to measure the elongation of the guitar string by utilizing the razor blade set-up as a barrier which also becomes a single slit when the string elongates. The results were then used in determining the Young’s modulus of the guitar string (accepted value = 2.1 GPa). A modified tensile test apparatus was used to determine the diameter d of a guitar string and the elongation L after adding loads at one end of the string. The values derived were used to determine the guitar string’s Young’s modulus. The derived Young’s modulus has the value of 2.20 ± 0.01 E+10 Pa.

Index Terms

young’s modulus, diffraction, laser, guitar string, diameter

Abstract

This study successfully employed a pore self-forming technique to fabricate red clay-based porous ceramics using binary mixtures of indigenous materials. Using a Least Square Method for Matrices, a binary proportion of the ceramic mixture based on a gehlenite phase (2CaO.Al2O3.SiO2) was calculated to consist of 48.15% Kauswagan clay and 51.85% limestone. The calculated binary formulation was varied as limestone-rich and red clay-rich mixtures with and without the addition of sacrificial template for comparison. The indigenous materials were calcined, dry pressed and fired at temperatures of 1175oC and 1200oC. The analyses of the fired porous characteristics of the fired formulations at 1200oC revealed that the calculated formulation without starch was better than that of the same composition with starch and varied formulations with and without the addition of starch. Specifically, the porous characteristics of the calculated formulation revealed bulk porosity of 52%, volume shrinkage of 22%, and diametral compression strength of 26MPa. A microstructural investigation into the fired porous ceramic body disclosed irregular pore morphology that is interconnected and surrounded with thinner cell struts representing high porosity.

Index Terms

Self-forming, Porous ceramics, Red clay, Porous fabrication

Abstract

The thermal conductivity of single layer and composite layer of materials was determined using the TD-8561 Thermal Conductivity Apparatus. The results for the single layer tests are compared with industrially accepted values and reveals the hierarchical order of the conductivity of materials (glass, plastic and wood) is with a good agreement (𝑘𝑔= 0.67±0.05 W∙(mK)-1), (𝑘𝑝= 0.24±0.01 W∙(mK)-1) , and (𝑘𝑤= 0.16±0.03 W∙(mK)-1). The results of the theoretical calculation for effective thermal conductivity of the composite layer materials (𝑘𝑒𝑓𝑓(𝑝𝑔)= 0.32-0.34 W∙(mK)-1), (𝑘𝑒𝑓𝑓(𝑔𝑤)= 0.21-0.26 W∙(mK)-1), and (𝑘𝑒𝑓𝑓(𝑝𝑤)= 0.14-0.17 W∙(mK)-1) also showed interesting results with composite layer materials consistent in terms of hierarchical order in both theoretical and experimental with glass-plastic (𝑘𝑒𝑓𝑓(𝑝𝑔)=0.41±0.08 W∙(mK)-1), glass-wood (𝑘𝑒𝑓𝑓(𝑔𝑤)= 0.36±0.04 W∙(mK)-1), and plastic-wood (𝑘𝑒𝑓𝑓(𝑝𝑤)= 0.29±0.02 W∙(mK)-1). The composite forms involving wood sample somehow produced results that deviate from the theoretical calculations. Observations during the experiment revealed that the wood had uneven surface and it was non isotropic in nature making the conduction process non-uniform and inconsistent. This was evidenced by the vapor condensing in the interface between the wood and the other substance. Thus, future test on composite materials must involve securing the optimum contact between samples and that the samples are isotropic.

Index Terms

conduction, composite material, effective thermal conductivity, industrial material, thermal conductivity

Abstract

Real-time object detection is essential for many Unmanned Aerial Vehicle applications such as surveillance and monitoring, search-and-rescue, logistics, and reconnaissance. However, the task of object detection in real-time is of great challenge and all the more so for onboard and embedded applications. This paper presents the performance of the Single Shot MultiBox Detector (SSD) MobileNet object detection model that is built on the TensorFlow framework when employed onboard an unmanned aerial vehicle. The onboard devices used are the Navio2 flight controller and a Raspberry Pi 3. The embedded software used are Ardupilot and Robot OS (ROS). Experimentation shows that by using SSD MobileNet, the UAV is capable of real-time, onboard multiple object detection.

Index Terms

Deep Learning, MobileNet, Object Detection, SSD, TensorFlow, UAV

Abstract

This study presents an analytical model of the helical structures of some globular proteins whose main chain have α-helical secondary structures in the framework of white noise path integral formulation. The winding probability for diffusive polypeptides is obtained using a drift coefficient or modulating function involving the convolution of Fourier cosine and sine functions of the form . Applications to some polypeptide chains are then explored where the formation of α-helices between their linear segments is compared to the conformation of these proteins found in the Protein Data Bank (PDB). The model incorporates chirality features of proteins and their helix-turn-helix sequence structural motif.

Index Terms

Alpha-helical proteins, Diffusion Coefficient, Modulating function, Protein folding, Winding probability

Abstract

Background radiation levels in four (4) selected schools in Cagayan de Oro City were measured using a portable Geiger counter that is capable of detecting alpha, beta, gamma, and X radiation. Data were collected during peak and off-peak times at four (4) identified areas of each school. The results showed that the measured background radiation level in all schools ranged from 103.19 to 107.58 cpm. These values fall under the significant radiation range which is between 100 cpm-10,000 cpm and beyond the threshold warning level for values above 100 cpm. It was observed that the school located at the center of the city and the one at the farthest had the highest and lowest radiation levels, respectively. From the results, the radiation levels in all schools were at their lowest values during the off-peak times. This study will serve as a source of baseline data for the selected schools as there are no previous radiation measurements conducted.

Index Terms

radiation, background radiation, school radiation, radiation level